Azalea plant named `Conlen`

ABSTRACT

A new and distinct variety of Azalea found as a seedling in a planned cross between the female Azalea `Red Slippers` and the male Rhododendron oldhamii `Fourth of July`. The new variety possesses a unique blooming time and is superior in development of an upright, dense, globose shaped plant with attractive single to semi-double strong red flowers.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct variety of evergreenazalea of the genus Rhododendron and a member of the Ericaceae family.This new azalea variety, hereinafter referred to as `Conlen`, wasdiscovered by Robert Edward Lee of Transcend Nursery in August, 1986 inIndependence, La. `Conlen` originated from a planned cross hybridizationbetween two selected breeding lines in a controlled breeding program inIndependence, La. The value of this new cultivar lies in its uniqueblooming period, bloom color, bloom form, bloom size, and growth habit.

Asexual propagation of the new plant by cuttings has been under Mr.Lee's direction at the same location. Several generations of the newplant have been evaluated and the distinctive characteristics of theplant have remained stable. The plant cannot be reproduced true fromseed.

SUMMARY OF THE INVENTION

The following are the most outstanding and distinguishingcharacteristics of this new cultivar when grown under normalhorticultural practices in Independence, La.

1. The unique spring, summer, and fall blooming.

2. A strong red flower color Red Group 46B with dotting color Red Group53A.

3. Single to semi-double flower range in size from 11/2"-2" in diameterand have wavy petal margins.

4. Easily propagated with semi-hardwood cuttings in late spring throughthe summer.

5. Fast growth rate under normal fertilization and moisture conditions.

6. Upright, dense and globose in nature.

7. Good specimen plant.

8. Desirable in planters.

9. Makes a very good low growing hedge or screen.

10. Very good foundation plant.

11. Does well as an understory plant in a woodland garden.

12. Hardy to Zone 7.

13. Attracts butterflies.

DESCRIPTION OF THE DRAWINGS

This new Azalea Hybrid variety is illustrated by the accompanyingphotographic prints in which:

1. FIG. 1 is a close-up showing flower, foliage, and stem color as wellas flower size and form.

2. FIG. 2 shows the dense, upright and globose growth habit of a threegallon plant.

The colors shown are as true as is reasonably possible to obtain byconventional photographic procedures. The colors of the various plantparts are defined with reference to The Royal Horticultural SocietyColour Chart. Descriptions of colors in ordinary terms are presentedwhere appropriate for clarity in meaning.

BOTANICAL DESCRIPTION OF THE PLANT

The following is a detailed description of the new variety of Azaleabased on my observations made of plants grown in wholesale commercialproduction practices, in greenhouses, and in established landscapeplantings in Independence, La.

    ______________________________________                                        Distintive Characteristics:                                                                                R. oldhamii                                      Charcateristic                                                                                                                             R.               ______________________________________                                                                             oldhamii                                 Height   4-5'      2-3'       8-10'   8-10'                                   (Mature)                                                                      Width (Mature)                                                                                                                                 6-7'         Flower Size                                                                            11/2-2"   21/2-3"   13/4-21/4"                                                                            13/4-21/4"                               Flower Form                                                                                                        Single                                                                   semi-double                                   Flower Color                                                                                                                                   Red G.                                            39A                                      Flowers per                                                                                                                                        2-4      Terminal                                                                      Bloom Period                                                                                                                                 Mid-May >                                           Mid-June                                 Bloom Period                                                                                     Late July >                                                                                                              Sporadic >                                           summer                                   Petal Number                                                                                                       5                                        Hardy Zone                                                                                                         8                                        Stamen                                                           7-10         Number                                                                        Stamen Type                                                                                                        Non-                                                                          petaloid                                 ______________________________________                                    

The female, or seed parent, of `Conlen` is the Azalea `Red Slippers`; apurplish red, single to semi-double, mid-season blooming, low compactgrower. `Red Slippers` is an unpatented Back Acres hybrid developed byB. Y. Morrison in Pass Christian, Miss. Mr. Morrison first introducedthese hybrids in 1964. His work was based on an interest inlate-blooming and double flowering clones. `Red Slippers` is the resultof the following cross: (`Andros`×`Parade`)×`Keisetsu`. `Andros`(unpatented) and `Parade` (unpatented) are Glenn Dale Hybrids and`Keisetsu` (unpatented) is a Satsuki Hybrid.

The male, or pollen, parent is Rhododendron oldhamii `Fourth of July`(unpatented) which originated from a R. oldhamii seed lot collected in1968 by Dr. Hsu of Taiwan University. The seeds were collected at 850meters elevation on Mount Tai Tun in Taiwan. Soon after this JohnPatrick of Oakland, Calif. was visiting Taiwan collecting plant materialof the Taiwanese Rhododendrons. He obtained a number of seedlings fromDr. Hsu and grew them in Oakland, Calif., in 1973, Dr. John T. Thorntonof C&T Nursery in Franklinton, La. obtained one of the Rhododendronseedlings from Mr. Patrick. Dr. Thornton noticed in the next few yearsthat this particular R. oldhamii plant was a perpetual bloomer from lateJune until frost on new growth. This plant produces two flushes ofgrowth containing flowers. The second flush of growth overlaps the firstflush producing a plant which blooms continuously. This differs from thespecies R. oldhamii which blooms from mid-May until mid-June andsporadically through the summer. Dr. Thornton subsequently named thisplant R. oldhamii `Fourth of July` in 1972.

The azalea `Fourth of July` seems to be hardy to about 10 degrees F.(zone 7). Temperatures below this cause dieback, but the plant readilyrecovers and blooms profusely the following summer. R. oldhamii is lesshardy at zone 8.

Robert Edward Lee's hybridization program was conducted with emphasis onspecies that are not commonly found in the genetic make-up of thepresent day hybrids. The `Fourth of July` cultivar which Mr. Leeobtained from Dr. Thornton in 1981 is a heavy summer and fall bloomingplant, not like the Rhododendron Species Foundation form. The flowerbuds form on new growth and start blooming about July 1. Mr. Lee usedthis species to cross with existing hybrids which have a tendency tobloom in the fall and which are also fairly hardy. As expected theresulting seedlings are heavy summer and fall bloomers with veryimpressive spring blooms also.

Classification:

Botanic.--Rhododendron hybrid `Conlen`

Form.--Upright, dense, and rounded

Height.--4-5'

Width.--4-5'

Growth habit.--Upright, dense and globose. Fast growth rate under normalfertilization and moisture conditions.

Growth rate.--In a period of six years from a rooted cutting the plantreaches a height of 3 feet and a spread of 3 feet. The growth rate isnormally about 8 to 10" per year; the plant reaches a height of 4 to 5'at maturity while maintaining a dense habit due to the abundant branchdevelopment.

Foliage.--Alternate, simple, evergreen, pubescent, elliptic, and varyingin size from 11/2" to 2" long and 1/2" to 3/4" wide. The margins areentire, with a petiole 1/4" to 3/8" long. Midveins and laterals areimpressed on the upper leaf surface and prominent on the underside. Thebase of the leaf is cuneate to attenuate and the apex is acute tomucronate. The upper surface of the immature leaves are dull, pubescent,and are Yellow-Green Group 144A and the underside is Yellow-Green Group146D, pubescent, and matte. The upper surface of the mature leaves areYellow-Green Group 147A, dull and slightly pubescent and the undersideis Yellow-Green Group 146B, matte, and pubescent. The immature petioles,midribs and veins are Yellow-Green Group 146C. New growth is pubescent.These hairs are initially soft and white and cover both sides of theleaf with a higher concentration on the petioles and veins. They areslightly curled, flat, and range in length from 1/32" to 1/8". As thegrowth matures much of the leaf pubescence is lost; however, the stems,petioles, and leaf veins retain this pubescence which becomes moresetaceous and darker in color (Brown Group 200A) through the growingseason.

In 1994, the date of initial spring growth was March 10, inIndependence, La. After the initial spring flush there was almostcontinuous growth until that fall ending October 23, also inIndependence, La. When grown in full sun, the internode length of thisplant is 1/4" to 5/8"; when grown in light shade the internode length is3/8" to 3/4". As would be expected a plant grown in shade results in ataller, less dense plant with larger leaves.

The average length of terminal growth of the initial spring flush isabout 5" for a plant in full sun and about 7" when grown in shade. Thisgrowth should not be trimmed since it will produce flowers starting inlate July. As the plant continues to grow through the summer and fallmore flower buds are produced, which mature and bloom until frost. Thisremaining growth produces about 4" to 5" of height. As cool weatherapproaches, some of the flower buds become dormant. These buds bloom inApril of the next year.

Stems: The young stems are Yellow-Green Group 146C and densely clothedwith spreading white glandular hairs. During the second growing seasonthey become Greyed-Green Group 197B, glabrous and rugose. The pith issolid and uniform. Young and older stems are densely branched.

Buds: Tight buds at 1/2" are ovate and acuminate Yellow-Green Group 146Dwith a hairy pubescence Brown Group 200A. The buds are borne in clustersof 2 to 3, and are sheathed by a pair of modified leaf bracts which arefrom 1/4" to 1/2" long, persistent, and Yellow-Green Group 147A. Thepedicel is 1/4" to 7/16" long, pubescent, and Red Group 53B. The calyxis 3/8" to 1/2" long, Yellow-Green Group 144A, funnel shaped,persistent, and pubescent. The five imbricated sepals are lanceolate andjoined at the base to form a cup. As the buds swell the bud sheathmatures to a Greyed-Orange Group 165A, falls off, and reveals the flowercolor Red Group 46B.

Flowers: Perfect, single to semi-double, Red Group 46B (front and back),glabrous, openly funnel shaped, 11/2" to 2" wide by 13/4" to 2" long,borne on current season's growth, non-fragrant; they last on the plantin the garden 5 to 6 days. There are 5 true petals which are fused atthe base, elliptic to obovate, and have wavy margins. The dorsal lobeand the two upper wings of these true petals are dotted Red Group 53A.There are 5 non-petaloid stamen which are 1/4" to 1" long and 5-10 shortpetaloid stamen 1/16" to 3/16" long. The filaments are Red Group 46C,the anthers are Red Group 46D, and the pollen matures to Yellow Group11B. The pistil is single, non-petaloid, 1" to 13/4" long and Red Group46B. The ovary is densely glandular-setose and has five locules. Thecapsule matures in about 5 months, in Independence, La., to about 1/4"to 1/2" long; it has a persistent style, is Yellow-Green Group 147A, andcontains from 100 to 400 nonwinged seeds. Normally fruit set is notheavy. There is a 2 to 3 week flowering period in April in Independence,La. Flowering resumes in late July as the new buds mature and continuesuntil frost which can be as late as November or December inIndependence, La. Azaleas blooming at this time of year attractbutterflies in profusion.

Culture: Grows well in a wide range of conditions, tolerates sun toshade. Prefers a moist, well-drained soil that is rich in organicmatter. Responds well to mulching and medium applications of fertilizer;prefers ph 5.0 to 5.5. Very little pruning is needed; adaptable tocontainer and above ground planters; makes a good foundation plant orinformal hedge with excellent foliage and flower contrast. Ideal forcoastal regions and warmer parts of Piedmont. Propagated withsemi-hardwood cuttings in late spring through the summer.

Pests: Lace wing and spider mites can be a problem.

I claim:
 1. A new and unique variety of Azalea plant named `Conlen` asherein shown and described.